Grease dispensing apparatus



Sept. 15, 1942. J. D MoRGAN Erm. Y.

' GREASE DIsPENs I NG APPARATUS,

Filed July 1s. i939 Ilm Patented Sept. 15, 1942 2,296,047 GREASE DISPENSING APPARATUS John D. Morgan, South Orange, and Thomas Anderson, Elizabeth, N. J., assignors, by mesne assignments, to Cities Service Oil Company, New York, N. Y., a corporation of Pennsylvania Application July 18, 1939, Serial No. 285,070

5 Claims.

This invention relates to viscous liquid dispensing apparatus, and more particularly to improvements in apparatus for feeding greaselto grease guns. The specific grease dispensing apparatus hereinafter described Was developed particularly for feeding grease directly under air pressure from a cartridge or can in which it was originally packed and shipped, to a gun such as described in Staples U. S. Patent No. 2,007,113.

Grease dispensing apparatus of this general type has been heretofore employed in which the original grease container or can is opened at each end and then mounted vertically in a twosectional pressure chamber having a grease outlet nipple in its base, the opening in the bottom of the can being aligned with the outlet nipple of the container and placed in sealing engagement therewith. For the purpose of unloading or displacing the grease from the can, a piston is inserted in the upper end thereof, the grease displacement being effected by application of compressed air pressure to the pressure charnber and to the piston, whereby the piston is forced downwardly toward that end of the can engaging the discharge nipple.

Apparatus of the type heretofore designed for dispensing or feeding grease in the manner just outlined has proved hazardous to careless operators by reason of the danger involved in breaking the seal and uncoupling the sections of the pressure chamber to obtain access to its interior without first reducing the airpressure which exists in the chamber during and following the grease feeding operation. In general,

such apparatus has also given trouble because of deformations which often occur in the light metal walls of the grease can and which inter-` fere with free movement of the piston. construction of the piston is also a serious source of diiliculty because of the tendency of the piston to bury itself in the underlying grease on application of air pressure, and because the piston is frequently ineflicient in performance of its principal function of displacing grease without bypassing grease and air.

The

' or bypassing of air and grease, and despite the fore, to provide an improved grease dispensing apparatus which is economical in design and can be rapidly assembled or taken apart, and 1n which the aforementioned defects are largely presence of slight deformations in the walls of thegrease container.

With the above and other objects and features in View, the invention consists in the improved grease dispensing apparatus which is hereinafter described and more particularly defined by the accompanying claims.

In the drawing,

Fig. l is a View in vertical section showing the principal elements of the apparatus in assembled relation after application of air pressure preparatory to the dispensing of grease from the original can; and

Fig. 2 is a cross-sectional view in reduced scale,

taken on the line 2-2 of Fig. 1.

Referring to the drawing, and particularly to Fig, 1, the principal elements of the apparatus comprise a cylindrical sheet metal or cardboard can or cartridge grease container III;. a cylindrical two-sectioned pressure chamber I2 dimensioned to accommodate therein the can I0 with sufficient clearance for easy insertion and removal; a coupling ring I4 by means of which a bell lid I6 and a dished base I8, which together make up'the sectional chamber I2, may be coupled together; a grease outlet pipe 20 leading out centrallyfromithe base of chamber I2 to a grease gun (not shown); an inlet port 22 for introducing compressed air into chamber I2; annular gaskets 24 and 26 for sealing the chamber I2 against escape of air therefrom; and a piston 28 slidably mounted in can III for the purpose of displacing grease from the can through outlet pipe 20.

Can I8 may be constructed of light sheet metal (24 gauge) with straight cylindrical sides joined to the ends (preferably recessed for stiffness) by outwardly rolled reinforcing ring joints 30. Both ends of the can IIJ are preferably provided with central apertures 32 which are designed to accommodate friction plug closures (not shown). In Fig. 1 the apparatus is shown with the base I8, the bell I8, and the coupling ring I4 and gaskets in the positions which they assume after sufficient air pressure has been built up in charnber I2 to raise the bell off its seat on the base.

Piston 28 is dimensioned to form a close sliding fit within can I0. For example, with a can of 9% inside diameter, the piston may have a diameter ele" less than that of the can. The piston is normally a disk of about 1/8" thickness, and according to the present invention should be constructed of mechanically strong material which is somewhat flexible and which has a specific gravity not substantially greater than one half that of the grease which is being handled. A preferred material for the construction of the piston is a corrugated paper sold under the tradename Kraftex (constructed of an inner corrugated layer 33 and two outside hat sheets 34 bonded together with silicate of soda). The faces of the piston are preferably coated with oil resistant wax or varnish. Such a corrugated paper piston has a specific gravity of only about 1/3 that of the grease, together with a bursting strength of 200 lbs. per square inch, and suiiicient flexibility so that its edges will yield to pass any deformation normally produced in the wall of the can I during shipment, while still retaining sufficient rigidity to perform its main grease displacing function without permitting substantial by-passing of air. Because of its light weight and the air pockets 35 characteristic of its construction, the piston will oat on top of the grease body while it is forcing the grease from the can under applied air pressure.

The base section I8 of the pressure chamber I2 is shown as a cylindrical dish-shaped vessel having in the center of its base a tapped aperture 36 with which grease discharge pipe 20 threadably engages. The top rim of the base I3 is provided with an annular squared outwardly projecting flange 31. An air supply pipe 38, equipped with an air supply valve 39 and an air release valve 46, threadably engages air inlet orifice 22 in base I8. The interior of the base I8 is preferably built up by means of an annular plate 42 to form an annular pocket 44 within which gasket Z6 is mounted, and to form an axial conical seat 46 for the edges of the bottom aperture 32 of can I IJ during the period when air pressure is applied to the apparatus. Gasket 26 (preferably constructed of rubber or of other flexible oil resistant material) functions as a centering seat for the bottom rim 38 of can I8, and as a seal against escape of .air from chamber I2 past the bottom of the can I0 into grease discharge pipe 28. The

gasket 26 is preferably so shaped and dimensioned that it will seat and seal cans I0 of varying dimcnsions, as for example, cans ranging in diameter from 81/2 to 91/2.

The bell lid I 6 of chamber I2 preferably has an inside diameter somewhat smaller than that of base I8. The bell may be of 1/8 thickness drawn ange steel, designed to carry a maximum working air pressure of 300 lbs. per square inch. Bell I6 is shown as provided at its top with a hand grip 48, and is fitted at its rim with an annular external ange 58 having at its outer rim an upwardly projecting annular locking ring 52. The bottom of iiange 58 is designed to seat on the top of ange 31 of the base member, and the top of iiange 58 cooperates with the bottom of ange 31 and with coupling ring I4 to form Ia safety lock coupling for the sections I6 and I8, preventing dismantling of the apparatus prior to the release of air pressure from chamber I2.

Gasket 24 has been illustrated as an annular ring gasket of substantially Y-shaped cross-section. The inside edge or rim of the flange 5l) has also been illustrated as tapering outwardly at a substantially 45 angle in the circumferential plane 54 where the bottom rim of shell I6 engages the stem section of the Y-sectioned gasket 24. One arm of the gasket 24 rests on the top surface of flange 31, and the other arm of the gasket hugs the inside top rim of base I8. Thus the gasket 24 forms a soft seat for bell I 6 on base I8 when there is no air pressure within chamber I2, and when bell I 6 is raised oi its seat by application of compressed air within chamber I2 (Fig. l), the stem and downwardly extending arm of gasket 26 are forced into tight sealing relation respectively with the portion 54 of the bottom rim of bell I6 and the inner wall of base I8, to prevent escape of air past the joint.

As shown best in Fig. 2, coupling ring I4 consists of two semicircular ring sections 56 (preferably of forged steel) which are permanently hinged together at one end by matching lugs 51 and a common hingle bolt 58, and which may be rapidly brought together and pinned at the swinging ends by matching lugs 59 and a locking pin 68. Each section 56 cf the coupling ring I4 is substantially C-shaped in cross-section, with that portion 6I of its concave inner surface which overhangs the bottom edge of ange 31 squared to match the flange, and with the top section of its inner surface which overhangs ring 52 having a depressed rim 62 forming an annular groove 63 which is shaped and dimensioned to match and lock with the top of ring 52 of flange 50 when the bell I6 is raised off its seat by air pressure applied to the chamber I 2. With this construction, therefore, it is impossible to disconnect the coupling ring sections I4 from the flanges 31 and 56 as long as there is sufficient air pressure in chamber I2 to lift the bell I6 from its seat on flange 31. At the same time the upwardly extending ring 52 of fiange 58 is of less height than the width of the space separating the bottom of the ange 50 from the horizontal arm of gasket 24 with the bell in its raised coupled position. Consequently, when there is no air pressure within the chamber I2, coupling ring I4 can be quickly swung into or out of coupling position with relation to flanges 5D and 31, with or without the use of pin 58 to hold the coupling ring sections in coupling position during the period when the bell I6 is seated on the top of flange 31. The coupling joint is preferably constructed so that the bell I6 is lifted about M3 olf its seat during application of air pressure to bring it into locking position with respect to the coupling ring sections I4.

The can I8 may be lled with grease while in upside down position to that shown in Fig. 1, with the top friction plug closure in place and with the bottom plug removed, and the piston 28 inside of the can, Iso that when grease is introduced the piston will lie at the bottom of the can in the grease filling position. After filling the can the top cover of the can is fitted thereto by the grease manufacturer preparatory to shipment. When the can is received by the operator of the grease dispenser, the first step is to remove the friction plugs from both end apertures 32, and to place the can in the air chamber I2, with that end of the can at which the piston 28 is located at the top of the chamber and with the bottom rim of the can seated on the gasket 26. The sections I8 and I6 of the air chamber are then assembled and the coupling ring I4 swung into place. Air pressure is then turned on to build up a pressure of about 300 lbs. within the chamber. The compressed air surrounds the can I0 and therefore bears downwardly against the piston 28, so that any pressure tending to co1- lapse the walls of the can is counterbalanced by the air pressure applied to the grease within the can. An unbalanced air pressure equal to the area of the friction plug removed from the aperture 32 at the base of the can serves to hold the can against its seat on the gasket 26 and to force the grease out of the can through the pipe 20. It will be noted that the coupling ring I4 and the flanges 31 and 50 are so designed that no circumferential stress is placed on the coupling ring during application of air pressure Within the chamber I2. The apparatus will operate over a considerable range of pressures, say for example pressures of 'T5-300 lbs. per square inch.

Having thus described the invention in its preferred form, what is claimed as new is:

1. A grease can unloading apparatus comprising a vertically disposed air cylinder having a removable lid anda base, an annular squared outwardly extending flange for the top rim of the base, an annular outwardly extending flange for the bottom rim of the lid adapted to seat on said base flange, said lid flange having an annular locking ring attached to its top rim, a split coupling ring of substantially C-shaped crosssection having an annular groove in that portion of its concave inner surface which overhangs the locking ring and adapted to form with the locking ring a safety lock coupling for the base and lid anges during periods of application of pressure to the air cylinder, and an annular gasket i of substantially Y-shaped section mounted as a sealing element for the coupling.

2. In grease dispensing apparatus including a sectioned pressure chamber having a dished base and a bell lid, theiimprovement in safety-lock coupling means for the chamber sections comprising a pair of outwardly extending annular flanges mounted respectively at the abutting ends of the chamber base and bell lid, an annular locking ring mounted at the top surface of the rim of the bell flange, a split coupling ring of substantially C-shaped section having a concave inner surface dimensioned to be moved easily into overhanging coupling relation above and below the bell and base flanges when in abutting position, and an annular groove in the inner surface of that portion of the coupling ring which overhangs the locking ring in position to contact and register with the locking ring on application of compressed air within the chamber tending to force the sections apart.

3. In grease dispensing apparatus including a sectioned pressure chamber having a dished base and a bell lid adapted to enclose an end-apertured cylindrical grease container in longitudinal position with a loose fit, said chamber having a grease discharge passage in the base in position to register with one of said container end apertures, a pair of outwardly extending annular flanges mounted respectively at the abutting ends of the chamber base and bell lid, a split coupling ring of substantially C-shaped section having a concave inner surface dimensioned to move easily into overhanging coupling relation above and below the bell and base flanges when in abutting position, said flanges and said coupling ring being shaped and arranged to form a safety lock coupling for the sections of the pressure chamber on application of compressed air within the chamber tending to force the sections apart, and a pair of annular gaskets mounted for setting up under pressure respectively to seal the pressure chamber against escape of air past the discharge end of the container and past the coupled flange joint of the pressure chamber.

4. In grease dispensing yapparatus including a cylindrical grease container having two oppositely disposed end openings, a multi-sectioned pressure chamber adapted to enclose said container land having a grease discharge passage in position to register with one of said container end openings, means operable by air pressure for coupling the sections of the pressure chamber together in tightly sealed and locked relationship, and a follower piston of substantial rigidity and strength slidably mounted in said container in position to be moved against the grease and toward the discharge passage by air pressure, said piston having a specific gravity not substantially exceeding half that of the grease and adapted to float on the grease.

5. Apparatus as defined in claim 4 in which the piston is constructed of three superposed layers of paper, the central layer being corrugated to add mechanical strength and to provide air cells within the piston for reducing its specific gravity.

JOHN D. MORGAN. THOMAS ANDERSON. 

